14Menstrual Cycle 2Can you complete the sheet “Menstrual Cycle 2”?
15The rest of today’s lesson (and tomorrow!) Know how a fertilised egg develops into an embryoKnow about implantationKnow how the developing baby is protectedKnow how the developing baby is supplied with food and oxygen and how waste is taken away.Know how long pregnancy lasts
19Sexual reproductionThe sex organs make sex cells
20Sexual reproductionIn male animals the sex cells are called sperm, made in sex organs called testes (testis is singular)I can stay alive in the vagina for up to 3 days waiting for an egg to be released.
21Sexual reproductionIn female animals the sex cells are called eggs, made in sex organs called ovaries.An egg is released from the ovaries about every 28 days. This is called ovulation.
22Sexual reproductionDuring sexual reproduction the sperm and egg join together (fertilisation)
23Sexual reproductionA fertilised egg is produced.
24Sexual reproductionThe egg cell begins to divide forming a ball of cells.Stem cells – have the potential to become any type of cell
25Sexual reproductionIt may take several days to reach the uterus and be implanted in the soft lining. It is now an embryo.
26After 8 weeks I am called a fetus. Sexual reproductionFinger–like projections grow into the uterus forming a plate like structure called the placenta.After 8 weeks I am called a fetus.
27Sexual reproductionThe umbilical cord joins the fetus to the placenta.
28The placentaIn the placenta food and oxygen diffuse from the mother’s blood to the fetus’ blood, and carbon dioxide and waste products diffuse the other way.
29The placentaIn the placenta the blood of the fetus flows close to the blood of the mother, but they do not mix.Why?
30The placentaIn the placenta the blood of the fetus flows close to the blood of the mother, but they do not mix.The mother’s blood under higher pressure would burst the vessels in the developing fetus.They may have different blood types.
31AmnionThe fetus is surrounded by a fluid-filled sac (amnion) filled with amnionic fluid. This protects the baby.
32Week 8 Baby's spinal column are beginning to form around week 5 Heart is beatingLungs are formedEyes and ears are developingAll internal organs are inplace by week 8Genital organs are visible
33Week 12 Inner ear, external ears, eyes, mouth and nose are developing Heart is pumping bloodto all parts of the body
34Week 16 Baby is now completely formed From now on, growth will be rapidHeartbeat can be heard with ultrasoundBaby's weight has more than doubled from week 15 to week 16Baby is moving quite vigorously
35Week 20 Baby is covered in fine hair Muscles are developing rapidly Teeth are beginning to formHair is growing on baby's headBaby is very active
36With special care I could survive if born now Week 24Baby can suck its thumbBaby can hiccup and coughBaby weighs just over 1 poundWith special care I could survive if born now
37Week 28 Vernix coats the baby's skin Baby's lungs are mature Fat is starting to accumulateBaby weighs approximately2 pounds
38Week 32 Most babies are in the head down position Baby weighs approximately 3.5 pounds
39Week 36 Baby continues to gain weight The irises of the eyes are now blueBaby weighsapproximately 5 pounds
40Week 40 Most of the vernix on the baby is gone Baby's eyes are open and it can distinguish light